BENEFICIAL INSECTS 63 



objects and then form an oval structure about themselves 

 by winding round and round a single thread a thousand feet 

 in length or thereabouts. The adult moth develops within 

 this cocoon and emerges in about two weeks if undisturbed. 

 To get the silk, however, it is necessary to kill the animal within 

 the cocoon, since if this is not done, the moth destroys one end 

 of it when it comes out. After killing the animal quickly in 

 boiling water or by dry heat, the loose silk is cleared away, the 

 end of the thread found and unwound. Over one hundred 

 million dollars are invested in silk industries in this country. 



FIG. 39. Honeybees. 

 A, worker; B, queen; C, drone. (After Phillips.) 



Honeybee. - - The honeybee is also a domesticated animal, 

 but it even now often returns to its former wild state, making its 

 home in a hollow " beetree." The number of bees in a pros- 

 perous hive is about sixty thousand. Most of these are sexually 

 undeveloped females, called workers (Fig. 39, A); a few are 

 males or drones (C), and one is the queen (B). The queen lays 

 all the eggs, the drones fertilize the eggs, and the workers carry 

 on all the activities of the hive. The wax out of which the 

 honeycomb is built is secreted by the glands on the undersur- 

 face of the abdomen of the workers (Fig. 40, A). The wax cells 



